A reminder of physical acoustics

Acoustics encompasses a variety of fields with very different approaches and techniques. When it comes to the perception of sound, there is an uncertainty that arises from individual variability. Events of acoustic origin impose themselves on human beings without any possibility of avoiding them. Auditory perception is thus based on physiological acoustics, in the knowledge that all the laws defining the psychological relationships between physical quantities and sensations are statistical laws, and the limits of validity appear as soon as the uncertainty becomes greater than the phenomenon to be measured. It is this last aspect, the purely physical aspect, the basis of the theory of sound production and propagation, that we will address in this article [R 3 112]. We will then apply this first part in particular to the environment and buildings, with the study of laboratory measurements. and in situ . Indeed, after decades of relatively slow development compared to other disciplines, building acoustics is now booming. This is the result not only of developments in metrological and computer technologies, but also of a definite demand and the resulting regulations.